Currently, many types of sprinklers are known and utilized for distributing water to a desired area such as for watering plants, crops, and lawns. Some sprinklers are generally stationary and deliver water to a predetermined area dependent on the direction to which one or more outlets, such as nozzles, are pointed. Many sprinklers rely on a portion that moves relative to a stationary or fixed base portion so that the water is distributed to a particular area intermittently as water is distributed to a different area.
For instance, some sprinklers rotate back and forth so, at a particular moment, a first area receives a certain amount of water while another receives less and, at a subsequent moment the first area receives less than the other area. Other sprinklers include a portion that includes one or more nozzles that rotate or sweep over a particular area so that, again, different areas receive water intermittently.
One type of sprinkler is known as a motor driven sprinkler. Though there are many types of these, one example utilizes a turbine placed in the water stream. When the water stream strikes the turbine, the water forces the turbine to rotate in a predetermined direction based on vanes or vaned portions located on the turbine. The rotation of the turbine then drives a portion of the sprinkler including a nozzle in a rotary fashion. Thus, the rotation of the turbine effects the rotation of the nozzle for distributing water in a radial fashion, and portions of the surrounding area receives water for the period of time in which a spray or stream of the nozzle is directed at the surrounding area portions.
Many motor driven sprinklers are pop-up sprinklers. A pop-up sprinkler is a sprinkler having a case or housing that is generally stationary relative to the ground, and a riser that is in a retracted position when the sprinkler is shut off and is extended when the sprinkler is activated by turning the water on. The riser reciprocates between the retracted and extended position within an internal cavity of the housing so that a nozzle located on the riser is free to distribute water when the riser is extended, while typically being located within the housing when the riser is retracted.
In a motor driven pop-up sprinkler, the riser includes a sprinkler head portion that rotates relative to the riser when in the extended position and activated. The riser contains a motor assembly which is connected to the sprinkler head such that the sprinkler head is driven around by the motor assembly. In many cases, this motor assembly utilizes the described turbine.
In use, the sprinkler head rotates upon the activation of water. Therefore, the sprinkler head rotates as the riser is extending from the housing, when the sprinkler head is extended, and as the sprinkler head is retracting as the water flow is diminishing before the water flow ceases. During this time, particulate matter may come in contact with and between the sprinkler head and the riser body. Such particulate matter may cause binding between the sprinkler head and the riser body.
In addition, people often grab onto the extended and rotating sprinkler head. This may be done by a person who is trying to adjust a setting on the sprinkler head or is trying to examine the sprinkler head. At times, the sprinkler head is held by a person with negative intentions, such as a vandal.
In the event the sprinkler head is held stationary or bound so that it is prevented from rotating, damage can occur to the sprinkler head. The components utilized between the motor and the sprinkler head operate in a wet environment, and using steel, for example, is often not beneficial to the life of the sprinkler head. On the other hand, the plastic or polymer components often used are typically not strong enough to halt the rotation of the motor assembly, such as the turbine in the water stream. The force of the water is great enough that the turbine continues to spin, and the internal components between the turbine and the sprinkler head can strip each other.
Accordingly, there has been a need for an improved motor assembly for preventing damage to a sprinkler head when rotation is impeded.